Oscillating fluid motor



y 1961 A. J. ROSENBERGER 2,984,220

OSCILLATING FLUID MOTOR Filed Feb. 20, 1956 INVENTOR. l/iiff/ Ea war-002 BY @a 450m YMM United States Patent "ice assignments, to Republic Flow Meters Company, Chicago, 111., a corporation of Delaware Filed Feb. 20, 1956, Ser. No. 566,433

4 Claims. Cl. 121-97 This invention relates to oscillating fluid motors and more particularly to a vane type fluid motor for adjusting the angular position of a shaft in response 'to fluid pressure.

One of the problems encountered in the use of vane type motors for control applications is the difliculty of providing a fluid tight seal around the vane and the shaft. While 'aslight amount of leakage is not critical for continuous operations, it is critical in positioning control applications. Another difficulty has been the construction of the motor housing so that it can be machined accurately and'economically with conventional tooling.

It is one o'f the'objects of the present invention to provide an oscillating fluid motor in which the vane "and shaft are securely sealed in the housing against fluid leakage. e I

'Anothe r object is to provide an oscillating fluid motor in which the vane is formed by two plates lying on opposite-sides of the shaft and slidably sealed againstthe inner surface of the housing by continuous sealing strips at the edges of the plates. This construction eliminates the necessity "for any shaft seals and enables the vane to be tightly --'sealedagainst the housing without creating excessive friction.

Afurther objectis to'provide an oscillating fluid motor in'which the housing is symmetrically divided into four parts for ease of machining.

According to one feature, there are two identical lower housingsections-and two identicalupper housing sections, the identical sections being secured together end-to-end for simultaneous machining by a lathe type tool and being secured together side-by-side to form either an upper orlo wer housing part.

The above and other objects and features 'of the invention Will'b'e more readily apparent from the following description whenreatl in connectionuviththe accompanying drawing, in which 2 Figure 1 is a top plan view with one of the upper housing parts removed of a vane type motor embodying the invention;

FigureZ isa side view with one side of the housing removed and with parts in section;

Figure3 is an end view with half of the housing shown in section; and

Figure 4 is-a section showing in detail mountingo'f the seals.

The motor-of the presentinvention comprises a housili g'indicatedgenerally at ltlhaving "a lower section indicated generally at 11 provided with an internal semicylindrical cavity of relatively large radius and an upper housing "section indicated generally at 12 formed with an internal semi-cylindrical cavityof smaller-radius. A shaft 13 extends transversely through the housing and is ouaaaued half in the upper casin'g part and half in the lower casing part with its axis on the center of curvature of the internal cavities in both casing parts. The shaft may be attached to any mechanism which it is 2,984,220 Patented May 16, 1961 desired to adjust angularly as, for example, a rotary type valve, or the like.

The shaft carries a vane which is adapted to engage sealingly against the interior surfaces of the housing and to be moved in response to fluid pressure differences on opposite sides thereof to change the angular position of the shaft and the mechanism to be controlled thereby. For this purpose fluid may be supplied to the housing on opposite sides of the vane through connections such as conduits 14 formed in the upper housing half under the control of external valves of any desired type.

According to one feature of the invention, the vane is made up of two plates 15 and 16 secured on opposite sides of the shaft 13. For this purpose, the shaft is formed internally of the housing with an enlarged trapezoidal portion 17 having flat tapering sides against which the plates fit and may be rigidly secured by fastenings, such as screws 18. I The plates are shaped to fit at their periphery closely adjacent to the interior surface of the housing and are recessed at their edges to receive packing strips, as best seen in Figure 4. With the plates properly secured to the shaft, the outer edges of the plates which extendinto the lower casing half will meet, as best seen in Figure 2, while the upper edges of the plates which fit into the upper casing half are spaced apart.

To seal the plates against the internal surface of the housing, continuous annular sealing strips 19 are provided fitting into the recesses in the edges of the plates, as shown in Figure '4. The sealing strips 19 may be of U-section, as shown, and may be formed of a material which will slide over the inner surface of the housing and which 'will seal against flow of fluid therepast. Suitable materials for this purpose include rubber, or one of the synthetic rubber compounds, as well as a number of common plastics, suchas nylon or the like.

To hold the sealing strips in place, fastening strips 21 fit overthe plates adjacent to their edges and are formed with downwardly turned projections 22 extending into the U-section of the sealing strips and pressing them tightly in the recesses in the plates. The strips 21 may be relatively narrow, as seen in Figure 3, and maybe secured to the plates "by spaced fastenings, such as bolts 23. With the 'sealin'gstrips mounted and sealing against the internal surface ,o'f'the housing, it will be seen that complete continuous seals are-provided around the edges of each of the plates so that possibility of leakage past the plates isminimizedor substantially completely eliminated. Since there is a ,plate on each side of the shaft, no packing's for the shaft are required andit can fit into cylindrical openings in the sides of the housing which are free of .packings and which can be conventionallyltibricated through fittings, as shown'at 24. .Accordingto one feature -of the invention, the 'housing is so designed that-it-can be'readily and accuratelymachined on conventional tooling such as a conventional lathe. 'Forthislpurpose the-lower half '11 of the hous mg is formed of-two identical sections 25 and 26 'each of which has flat flanges 27 at its side edges and flat flanges 28 at its ftop "edges for-assembly. In forming-the lower'half 0f the-"housing, two identical housing sections may have the faes "of their fla'nges 28 machined flat and the flanges -28 may be secured together by bolting with thehousing halves in end-to-end relationship. "The internal surfacehf-the{housing may then be machined on a conventional lathe type tool with "the center of rotation of the'toolc'oaxialwith the ultimate positioning of the shaft 13 relative to the housing parts. It will be seen that with the housing parts connected together endto-end a lathe type tool can make a complete circular out which is dish shaped and ofwhich the two halves are identical.

With the housing halves so connected, the faces of the flanges 27 can be machined flat and the housing halves can then be separated and reassembled side-byside with the flanges 27 facing each other and can be secured together to complete the final assembly of the lower housing part. In the final assembly, the faces of the flanges 28 will lie accurately in a common plane and the internal surface of the lower housing half will be accurately concentric with the shaft 13. I The upper housing half may be formed in the same manner by taking two identical castings each corresponding to half of the upper housing half and securing them together end-to-end for machining. After machining the upper housing sections can be secured together side-byside to complete the upper housing half. To complete the assembly, the shaft and vane previously assembled are inserted in between the housing halves, which are then connected together through their end flanges. In the event it is necessary to disassemble the housing for replacement of seals or the like, the upper housing half can be removed from the lower housing half for easy removal of the shaft and vane assembly without disassembling the several sections.

While one embodiment of the invention has been shown and described herein, it will be understood that it is illustrative only and not to be taken as a definition of the scope of the invention, reference being had for this purpose to the appended claims.

What is claimed is:

1. An oscillating fluid motor comprising a hollow housing, a shaft extending rotatably through the housing, the upper and lower internal surfaces of the housing on opposite sides of the shaft being formed as surfaces of rotation about the shaft axis, the radius of the lower of said surfaces being substantially greater than the radius of the upper of said surfaces, the cross section of the part of the shaft within the housing being in the form of an isosceles trapezoid in cross-section with its opposite sides at an acute angle to each other converging in the direction of the lower surface, a pair of rigid flat plates secured to said flat nonparallel sides of the shaft respectively with their edges lying adjacent to the internal surfaces of the housing and with their edges remote from the shaft at one side thereof meeting, and a pair of continuous sealing elements, one mounted on each of the plates and extending about the periphery thereof to seal its edge slidably against the internal surfaces of the housing.

2. An oscillating fluid motor comprising a four section hollow housing, a shaft extending rotatably through the housing, the internal surfaces of the housing being formed as surfaces of rotation about the shaft axis and symmetrical with respect to mutually perpendicular housing section parting planes one of which includes and the other of which is perpendicular to said shaft axis, vane means secured to the shaft within the housing and slidably sealed against the internal surfaces of the housing, the housing four sections comprising two identical lower sections terminating in a flat upper surface in the plane of the shaft axis and two identical upper sections dilferent than the lower sections and terminating in a flat lower surface in the plane of the shaft axis, each of which terminates in two flat connecting surfaces at right angles to each other, the two sections of each identical pair being connectible end-to-end at said one of said parting planes to form a cup shaped member symmetrical about the axis of the shaft and being connectible side-byside at said other of said parting planes to form a hous- 4 ing part having a semicylindrical internal surface whoseaxis lies on the shaft axis.

3. An oscillating fluid motor comprising a four section hollow housing, a shaft extending rotatably through the housing, the internal surfaces of the housing being formed as surfaces of rotation about the shaft axis and symmetrical with respect to mutually perpendicular housing section parting planes one of which includes and the other of which is perpendicular to said shaft axis, vane means secured to the shaft within the housing and slidably sealed against the internal surfaces of the housing, the housing four sections comprising two identical lower sections and two identical upper sections different than the lower sections and terminating in a flat lower surface in the plane of the shaft axis, each section having flat fastening flanges at right angles to each other at one end and one side, the end flanges on identical sections fitting together at said one of said parting planes to define a cup shaped member symmetrical about the shaft axis and the side flanges being connectible at said other of said parting planes to form a housing part having a semi-cylindrical inner surface coaxial with the shaft.

4. A housing for a pivoted vane type oscillating fluid motor comprising a pair of complementary identical cast lower housing halves and a pair of complementary cast upper housing halves rigidly connected at mutually per pendicular parting planes to define an enclosed chamber bisected transversely by one of said parting planes and longitudinally by the other of said parting planes and having a lower portion of semi-cylindrical form and an upper portion of semi-cylindrical form of smaller crosssection than the lower portion and concentric therewith; said lower housing halves defining an open topped recess having spaced parallel finished side walls and a semicylindrical finished end wall extending between and joined to said side walls by large radius fillets, the parting planes between said lower housing halves being parallel and equally spaced from said side walls; said upper housing halves defining an open bottom recess having spaced parallel finished side walls coplanar with the respective side walls of the lower housing recess to form upward upper housing recess semi-cylindrical wall being concentric with the lower housing recess semi-cylindrical wall and the parting plane between said upper housing halves being coplanar with the lower housing half parting plane.

References Cited in the file of this patent UNITED STATES PATENTS 917,092 1,178,695 Yost Jan. 8, 1915 1,639,043 Malouf Aug. 16, 1927 1,950,276 Taylor Mar. 6, 1934 1,978,634 Hueber Oct. 30, 1934 1,989,846 Christman Feb. 5, 1935' 2,055,739 Wilhelm et al Sept. 29, 1936 2,467,121 Ferris Apr. 12, 1949 2,553,973 Keller et a1 May 22, 1951 2,564,206 Johnson Aug. 14,1951 2,612,874 Deibel Oct. 7, 1952v 2,612,875 OShei Oct. 7, 1952- 2,613,121 Oishei et a1. Oct. 7, 1952 2,698,607 Krohm Jan. 4, 1955' 2,752,664 Brown July 3, 1956 FOREIGN PATENTS 338,872 France June 17, 1904 Miller et al. Apr. 6, 1909 

